MSA and scuba tanks

(Not air tank certified but, current full time Firefighter.)
I tend to see things in black and white. There is a life span on these bottles. That life span was put in place for a reason. It's not worth the risk to me.
The way we treat our bottles, it would be easy to justify extending that life span... They're not abused, always cared for, never in any hazardous environment, not knocked around, not stored in extreme temp changes.... 
I have heard that Europe uses the same bottles for 30 years but, I can't confirm it. I've also heard that if you hydro on year 14, you can scratch another 4 years out of the total life span. 
Treat them like bombs. There is a lot of potential energy stored in those bottles. Err on the side of caution. You might not be shooting at all if you get injured. 
That's just my 2¢ on it. 
PM sent
Tom

I agree with Tominco. It's not worth it. High pressure air must be respected. 

I think a SCBA tank has a max life span of 15 years. 

What at is the life span of a steel scuba tank?

5 year hydrostatic tests but is there a max time limit like an scba tank?

I've been SCUBA certified for over 35 years and I have yet to know of a life span for a steel or aluminum SCUBA tank as long as they can pass a hydrostatic test every five years. To my knowledge it is only the composite skinned tanks that have the 15 year life according to DOT requirements. It should be easy to tell if your MSA tanks are metal or composite on the outside but the real test is whether the hydro dates are stamped in the metal at the top (metal tank) or a sticker on the side (composite tank). If you are still unsure take them to a paintball refill station or SCUBA refill location because as has been said before those tanks have a lot of stored energy in them when full and are like a bomb or a rocket if they rupture !!

I agree, that caution should always be exercised when using any tank. But the reason for my question is that I am not aware of a max time limit, like the scba tanks.

Five year hydro tests, should insure you are using a safe tank. Naturally, a visual, and checking the valve for proper operation etc.

I just had my two steel Faber tanks hydroed, i bought these tanks new 5 years ago, and have been using them to fill my guns, they have never been in the water.

I brought them to the facility that hydros them, and 21 dollars each, 3 day turn around.

One is an 80, the other is a 117 cu ft tank, both are rated at 3442 psi, i fill them to 3200 and use a cascade system with them.

If buying a used tank, it is good to know the history, if possible, and a current hydro would be my requirement.

The scuba tanks are designed to have an indefinite life. (as long as they pass hydro and visual inspections) Now with that said the DOT has issued recalls on certain DOT certified tanks to be taken out of service (or limited service requirements). There are a number of websites that have the details of the DOT certification numbers that have been recalled. You will find the particular certification that your tanks are manufactured to on the neck of the tank right after the "DOT xxxx" You can do a search on that number and see if there are any recalls or new requirements of service that may impact your particular tanks. Hope this helps. 

Im here in euroland and we mainly use 300 bar steel tanks, on first fill the guy at the diving club asked me about the age and I said brand new, and asked about the time limit on it.

"for your use, forever." 

So I guess divers use a lot of old crummy tanks.